Tool-holder.



W. S. ROBINSON.

TOOL HOLDER. .APPLlcATloN FILED Aus. u. l'1911.

Patented Spt. 3, 1918.

WILLIAM-sfBOBINSON,0F CHICAGG, ILLINOIS, VASSIGNOR TO-AR1VISTRONG-BROSi TOOL CGMIANY,'- OF CHIC'AG-D, :ILLINOIS,-A CORPORATION OF ILLINOIS.`V

TOOL-HOLDER.

LZTASL Speccatjonof Letters Patent;

Patented Sept, 1918.

Application filed .August 1,1, 1917. Serial No. 185,666.

To allpwwm z'may, concern:

Be it known that LTWILLIAM S.' ROBIN- son, a 4citizen of the. United States., resid-'- ing at Chicago, in the countyof .Cook and.

State of Illinois, have invented certain new and useful Improvements in Tool-Holders,`

of whichlthe followingvisa specification;

The invention relates to tool holdersl of the:

type employed upon` lathes and other metal working machines, wherein it frequently belcomes desirable, as in cuttingthreads, ,to

permitthe cutting tool to yield slightly ,durf ing the cuttingoperation, in order to pro` duce a nicelinishupon the work, andat other times it is preferred uto rigidly` hold the tool .to the work; and the general object of the invention is to provide. a. `tool holder which may be readilyfconverted from a rigid into a resilient holder, and viceversa.

A more specific object of the inventionis to provide, in combination Vwitha resilient tool holder having-a sectional clamping holder at all times so that it cannot become.

lost or misplaced when not in ruse..

The objects ofthe invention thus gener-4 ally stated are attained by providing on one end of the shank 'of-a tool holder an inverted VUlshaped portion .orneck having ,a sectional head on its end ladapted `to secnirely` sup port a tool and` lto .release the tool without being disassembled, and adjustably' mount-A ing in the -end ofthe shank below the` neck a stop` screw adapted to be screwed into engagement. with'a removable section ofthe head to serve as a stay or brace between the head and the shank when it is desired thatv thegtool be rigidly supported by theholder. A, preferred embodiment of .my `invention is illustrated inthe accompanying drawings formingpart hereof in whi'ch "Figure l is a fragmental side elevation7 offmy. time proved tool holder. Fig. 2 isa fragmental underside `,plan view of the tool holder.

Fig. 3 is a sectional view on line 3-173 F l. Y Fig.l L `is a fraginentalside'elevation of a slightly modified 'form of 'tool 'holdein Fig. 5 is a sectional viewon line 5--5,l Fig. .4.

Similar numerals refer to similar parts throughout the drawings.

The tool holderrconsists of a shankl, a sectional tool clamping head 2 carriedonl the end of an inverted. Uf-shaped neck` 3 formed on one end of the shank, and a stopscrew 4 mounted ,inthe end of the shank below the neck and` adapted to be screwed into and out-fof engagement with the head.

The shank 1 of the tool holder is in the form of a rectangular bar adapted to be mounted in the tool post or holder (not shown) ofa lathe or the like, and the head 2 which may be made cylindrical in form is supporteduprightly upon the free or forward end of the neck 3 which is formed integrally with the shank.

The head 2 is'preferably made in sections; consisting of an upper section or jaw 2, and a lower section or jaw-2b.

The upper jaw is'preferably formed integrally with the neck 3 and the lower jaw is provided withia central upright Vstem 5 extending,upwardly throughan aperture G in the upper jaw and provided `with a nut 7 on its threadedend by means of which the two jaws are adapted to be clamped together. The upper portion of the. lower jaw 2",is provided with a transverse groove 8 which is partially closed` by the lower end of thestem 5 formed on the jaw and said stem. is also slightly-grooved on its under side as shown at 9, Fig. 3, to permit the in-f sertion of a tool A of slightly greater thickness than the depth of the groove 8 in the jaw 2b. It'will thus be evident that a small portion of the tool A will protrude above the upper surface of the lower jaw at each side'of the stem so that when the .two jaws of the head are clamped together by means ofthe nut 7 on the stem 5 the lower end of the upper jaw 2u will engage with the upper surface of the tool and. securely. hold itin position in the. groove 8. `Preferably the lower end of thestem 5, as it is formed upon thelower jaw 2b, 'has an enlarged portion 10 having la tapered upper surface, and the aperture 6 of the jaw 2a iscorrespondingly enlarged and shaped as at Ga'to receive the portion 10. This construction affords an improved bearing for the stem in the upper jaw.

The neck 3 for supporting the head 2 on the shank 1 is adapted to hold a tool in the head with a substantial degree of rigidity, but at the same time is sufficiently reduced in size from that of the shank upon which it is formed to permit a slight longitudinal yielding of the tool in case a hard and unyielding substance is encountered by the tool in the work, or in case a cut of unusual depth is made by the tool. Such yielding of the tool is advantageous where it is es sential that a nice finish be produced upon the work.

It is sometimes desirable to rigidly mount the tool in the lathe and in such event it becomes necessary to employ a tool holder which is not resilient. Iu order to avoid the necessity of employing` a separate tool holder for this purpose I have provided means for staying or bracing the head against a yielding movement and thus enable a tool holder to rigidly support the toolfor engagement with the work. Such means consists of the stop screw il. which is entered through a threaded opening 11 in the forward end of the shank 1, below the neck 3. Such screw is preferably knurled as at 12 and is adapted to be screwed into and out of engagement with the lower jaw f1." of the head. The screw is made of such length that it cannot be removed from the shank without disassembling` the head 2, and the lower end of the jaw 2b of the head is preferably made in the shape of a regular polygon, as at 13, in order to afford flat bearing surfaces for the forward end of the stop screw in various positions of adjustment of the tool A in the head.

It will thus be seen that the stop screw is readily adjustable into or out of engagement with the head so that the tool holder is readily convertible into either a rigid or a yielding holder, as may be desired, and at the same time the screw is retained in the holder at all times thus avoiding any danger of losing the screw due to the removal of the same in making a change from a rigid to a resilient holder. Furthermore, only a slight movement of the screw is necessary to change the holder into the desired form owing to the comparatively slight extent to which the tool is caused to yield, and thus the operation of converting the toolholder from one form to the other is extremely simple and easy.

In Figs. -t and 5 I have shown a slightly modified manner of mounting the tool A in the head of the holder without interfering with the operation of the `stop screw. In this instance the tool is mounted in transverse grooves S' and 9 formed at one side of the jaw 2b and the stem 5 respectively, the tool and grooves being preferably beveled downwardly and inwardly at their lower edges in order to prevent the tool from slipping laterally out of the grooves.

I claim as my invention 1. A tool holder including a shank, sectional means for yieldingly supporting a tool upon one end of the shank, and a member carried by the shank movable longitudinally thereof into and out of engagement with the tool supporting means, said` member being irremovableV without wholly disassembling the tool-supporting means.

2. A tool holder including a shank hav ing a resilient neck, sectional means for supporting a tool carried by the neck, and a member carried by the shank movable lon gitudinally thereof into and out of engagement with the tool supporting means, said member being irremovable without wholly disassembling the tool-supporting means.

3. A tool holder including a shank, a head for supporting a tool comprising a fixed section and a removable section, a resilient neck connecting the head to the shank and supporting it at substantially right angles thereto, and a stop screw in the end of the shank adapted to be screwed into and out of engagement with the removable section of the head.

4. A tool holder including a shank, a sectional tool supporting head yieldingly mounted on the shank, and a stop screw in the shank adapted tobe screwed into and out of engagement with the head, said stop screw being irremovable from the shank without disassembling the head.

5. A tool holder including a shank having a resilient neck; an upright sectional head including a fixed upper section and a removable lower section, and means for clamping the sections of the head together with a tool therebetween; and a stop screw in the shank adapted to be adjusted into or out of engagement with the lower section of the head, said screw being irremovable from the holder without wholly disassembling the head.

6. A tool holder including a shank having a resilient neck; an upright sectional head including an upper jaw and a lower jaw, and a stem on the lower jaw entered through the upper jaw and having a lock nut threaded on its upper end for clamping the jaws together, there being a transverse groove in the lower jaw adapted to receive and hold a tool of greater thickness than the depth of the groove when the jaws are clamped together and to release the tool when the jaws are unclamped without disassembling the head; and a stop screw in the shank adapted to be adjusted into and outof engagement with the lower jew of the head, the lower end of the head being the head, said screw being irremovable from removable to enable the insertion of the 10 the holder without disassembling the head. screw into the shank and provided with a 7. A tool holder including; a shank, an plurality of Het. bearing surfaces on its pe- 5 upright head for supporting e tool, a resiliriphery for engagement by the stop screw.

ent neck connecting the head to the shank, In testimonyT whereof, I have hereunto and a stop screw in the shank adapted to set my hand. be screwed into or out of `engegement with WILLIAM S'. ROBINSON.

Copies of this patent may be obtained for iive cents each, by addressing the Commissioner of Patents, Washington, 1D. C. 

